Check the maximum speed for your tires.

The rating tables for tires are not just 'limits.' They express the MTBF which is essential to the design and manufacture of the tire.

For example, if a tire is speed rated at a maxiumum of 65 mph, at about 72.5 mph it is being run at one Standard Deviation above the maxium rating. At 79.5, two Standard Deviations.

Ratings aren't just guidelines with tires, IMHO, they are predictive of what to expect going down the road. Not calculated into the tire manufacturer's guidelines is the application: Most Prevost coaches I know of have a 'time' delay in the suspension, which means that they will roll for a bit before the air suspension system corrects the roll and straightens out the coach.

So, at speeds higher than rated, what occurs is that one has a 20-25 ton chunk of technology basically out of control on a corner...and that doesn't include the additional dynamic of trying to stop or slow down.

Let the trucker yell at me. it wouldn't be the first time (BTW they don't have the 'time' delay system in their suspensions, so that's not an apt comparison).